In the practice of veterinary medicine radiographs of the distal limb are common and necessary for diagnostic and research purposes. Accuracy is critical when positioning the collimator relative to the specific area of interest. In most cases it is necessary to elevate the horse's foot off of the standing surface to allow the foot to be centered in the cassette and the x-ray beam to pass horizontally through the solar surface of the foot, the DIP joint, navicular or other area of interest. The height of the elevation platform that the horse stands on during the radiographic examination must be adjustable to insure a horizontal beam through both the upper and lower aspects of the limb. The height is also a function of the size and configuration of the radiograph machine.
The prior art has recognized the need to elevate the foot being X-rayed but the simplistic approach of employing one or more wooden pads to act as the elevation platform has disadvantages and dangers. The elevation platform for the foot must be narrow enough for the cassette plate to be positioned close to the foot when taking a lateral view in order to control accurate proportioning. The same is true with the length of the pad so that proportioning can be controlled during a dorsal-palmar view. But getting a horse to stand on the required small pad while technicians and equipment are being moved around its feet is not only frustrating but can be dangerous. Acquiring views of the hind feet is even more complicated and dangerous. A highly stressed or nervous horse is apt to fall or step off of the pad with possible injury to the horse and probable damage to the expensive image collector and radiograph equipment. In some cases sedation of the patient is required to insure a successful radiograph. While sedation may be helpful, it is not without risk of harm to the horse or human attendants, not to mention the added expense and time involved.
The prior art includes a multitude of pads for the feet of horses but most are nailed or otherwise semi-permanently attached to the hoof and are fixed in their height. U.S. Pat. No. 120,119 discloses a vertical standard to be placed beneath the horses hoof with a lever, operated by the blacksmith, to elevate the horse's hoof to facilitate shoeing the elevated foot. U.S. Pat. No. 6,443,231 discloses a releasably mounted sock having one or more risers secured to the sock for elevating one foot of a horse to encourage the horse to lift the opposite hoof for shoeing. The prior art does not teach or suggest a method for attaching a variable height pad to a horse's hoof for purposes of conducting a radiographic examination of areas of the horse's lower limb.
Accordingly, it is the primary object of the present invention to resolve much of the risk and wasted time associated with prior art methods and apparatus for elevating a horse's foot for radiographic examination.